Researchers tested more than 150 2011-model infant, convertible, and booster car seats for the presence of potentially harmful chemicals including brominated flame retardants, polyvinyl chloride (PVC), lead, and heavy metal allergens. These chemicals have been associated with reproductive and developmental health problems and certain cancers in animal and some human studies.

The researchers note that the tests were performed on a limited set of chemicals of concern. Tests were not performed for certain other potentially harmful chemicals such a chlorinated flame retardants (CFRs).

Some car seats such as the Graco Comfort Sport in Caleo are virtually free of the toxic chemicals tested, while others such as the Britax Marathon 70in Jet Set contain potentially hazardous chemical combinations. “Poor performing car seats have hazardous flame retardants and may have one or more chemicals such as lead or vinyl-coated fabric,” says study researcher Jeff Gearhart, the research director of healthystuff.org, a project of the Ecology Center.

“Car seats should be used regardless of what our test results show,” he says. The new data can be useful when shopping for a car seat, he says.

“It is very important to understand that these are chemicals in synthetic materials that are present throughout our environment,” not just in car seats, Gearhart says.

Overall, brominated flame retardants were present in 44% of the car seats that were sampled, and 60% of the car seats tested positive for one or more toxic chemicals, the report showed.

The levels do seem to be decreasing when compared to previous reports. In 2009, 63% of the car seats contained brominated flame retardants. The average ranking of car safety seats has improved by 64% since 2009.

Report Ranks Child Car Safety Seats

According to the new report, the child car safety seats with the most hazardous chemicals in each of the three categories include: